Even though they said that they wont press charges is there still a possibilty that they will?
yes

and will this be on his record to the point where it will effect him getting future jobs?
if the police are involved, yes. If the police are not involved, it would be on his personnel record at CVS. I would suspect CVS is not going to provide a glowing recommendation

can they still come and arrest him?
yes

what do we do from here?
not much to do. Don't speak with anybody about this. Anything said can come back to haunt him if criminal charges are sought.